news this morning, an increasing number of lawmakers are expressing concern of the obama administration's use of drone strikes. the concern stems from new evidence on how much authority the administration believes it has to kill suspected terrorists, even if they're american citizens. abc's jon karl reports. >> reporter: a newly disclosed justice department document say american citizens tied to al qaeda can be killed, if, quote, an informed high-level official believes the target poses an imminent threat. but the document says it, quote, does not require the government to have clear evidence. case in point, anwar al awlaki, an american citizen and top al qaeda leader, linked to several terror attacks. he was killed in a 2011 drone strike. human rights advocates say the justice department memo goes way too far. and -- >> justifies, essentially, a claim that the executive branch can be judge, jury and executioner. >> reporter: as soon as he became president, barack obama stopped cia tactics like waterboarding, that he considered torture. but this justifies outright killing of a suspected
